powerpc/pseries: Move mm/book3s64/vphn.c under platforms/pseries/

hcall_vphn() is specific to pseries and will be used in a subsequent
patch. So, move it to a more appropriate place under
arch/powerpc/platforms/pseries. Also merge vphn.h into lppaca.h
and update vphn selftest to use the new files.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

tools/testing/selftests/powerpc/vphn/Makefile

@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 TEST_GEN_PROGS := test-vphn
 
-CFLAGS += -m64
+CFLAGS += -m64 -I$(CURDIR)
 
 top_srcdir = ../../../../..
 include ../../lib.mk

tools/testing/selftests/powerpc/vphn/asm/lppaca.h

@@ -0,0 +1 @@
+../../../../../../arch/powerpc/include/asm/lppaca.h

tools/testing/selftests/powerpc/vphn/vphn.c

@@ -1 +1 @@
-../../../../../arch/powerpc/mm/book3s64/vphn.c
+../../../../../arch/powerpc/platforms/pseries/vphn.c

tools/testing/selftests/powerpc/vphn/vphn.h

@@ -1 +0,0 @@
-../../../../../arch/powerpc/mm/book3s64/vphn.h